As it says on the about page of this blog, I am an engineer and scientist and rather technically inclined when it comes to my photography. Especially when it comes to my analog photography, and photo chemistry is a large part of that indeed. On advice of a member of the dutch ‘Analog Only’ facebook group, I purchased ‘Developing, the negative technique’ by K.I. Jacobson and R.E. Jacobson (ISBN 0 240 44770 0). Specifically, I got the eighteenth revised edition that was printed in 1976. I ordered it from a secondhand dealer via for €3,86 including shipping. A real steal if you ask me, as my copy is in near-mint condition. But, for those that rather read from a screen: you can also read the 1972 edition online. Below you will find my review of this book, which I think should be on your dark room bookshelf.


Already in the front matter, the authors show that they mean business. The title page lists the academic degrees of the authors in capitals: Ph.D and M.Sc. Ph.D. A.R.I.C. for K.I. and R.E. Jacobson, respectively. This is not something I have seen before in a photography book, and struck me as odd. Clearly, these are not just photographers, these people have a well founded background in the underlying science and they want you to know.

The book was first published in 1940 and has since then undergone both minor and major revisions to keep up to date. For most purposes of today’s dark room work, the information is certainly not outdated and of much use to both beginners and those more versed in chemistry. Especially since this edition was printed in 1976, it is pretty up-to-date with the state of the art, which hasn’t undergone major changes since. Some processes that are discussed have disappeared, or have been finetuned, but the underlying physics and chemistry is still the same as it was then.

The writing style is clearly academic and may need some getting used to. Although all important concepts are explained step by step and illustrated with good graphs and examples, this is not a book you want to read right before going to sleep. I was told the book is or used to be part of the standard curriculum of many photography classes at college/university level. For example, sentences such as: “Gamma is the tangent of the angle produced when the straight line portion of the characteristic curve is prolonged to meet the horizontal axis.”, may scare off the casual reader. However, I recommend that you keep on reading and take your time to digest the contents, because there is much to be learned here.

Figure 1: Sample of the illustrations in the book.
Figure 1: Sample of the illustrations in the book.

Looking at the table of contents, it is clear that the book is arranged by topic and that the topics ordered from by level of difficulty; basic concepts and black and white developers in the first half, retouching and colour developing in the second. As the chapters are unnumbered and cross-references to figures, tables and page numbers for more information are given throughout the book, it is not necessary to read it in chronological order. Although I would recommend that you do on your first read. The book counts more than 20 chapters, so allow me to only discuss the ones that I found most interesting.

Setting the stage with concepts and processes

The second chapter of the book, “Emulsion sensitivity and gradation”, dives straight into characteristic curves and gamma values. Even though in every day practice the amateur darkroom printer rarely is concerned with these concepts, or feels a need to do accurate measurements of densities using a densitometer, they are important for the rest of the book and the general understanding. They are referred to often in later chapters of the book.

This chapter is quickly followed by “Image structure”, in which the authors discuss the characteristics of grain, image sharpness and resolution in both negative and print, but also optimum exposure. It is instructive to read these carefully, because it helps visualize the effect of other chemical components better.

Developer talk

The chapters that are most important to those interested in photographic chemistry, are appropriately titled “The progress of development”, “The composition of the developer” and “Developer formulae”. In roughly 100 pages, the chemical processes ongoing during development are captured, as well as the main components of each developer. Where the authors start by explaining the functions of the individual components of a typical formula, they continue by listing well over a hundred different formulae and their characteristics. The formulae are grouped by application, such as “general purpose”, “extra fine grain”, and “tropical developers”. Per category the main differences between the listed compositions is discussed, and where necessary their specific uses are highlighted. What might be especially interesting, however, is the concluding table at the end of this chapter. This table of “basic developer” formulae, condenses the key ingredients and ratios of all formulae of a given category and brings it back to a single master formula. Although these are not necessarily tuned to a specific family of films, they result in working formulae that should be great starting points for your own experimentation.


After the developer and the stop bath, the process continues with fixing. This step removes the remaining light sensitive silver bromide from the emulsion and thereby ‘fixes’ the image. The authors have a single chapter dedicated to the topic to discuss the physical and chemical processes, a handful of formulae and some practical considerations for checking if the working solution is still fine for use. Especially interesting to me, is the brief discussion on monobath developers that use a fine balance between developer and fixer in a single solution. Projects such as New55, which are trying to remake the infamous Polaroid Type 55 film, rely on monobath developers. The discussion is brief though, and the authors recommend that G. Haist wrote more authoritative works on the topic.

An extra point of interest, is a discussion on the methods that are available for the recovery of silver from the fixing solution. This is not as much interesting from an economic point of view as it used to be 30 years ago, but it is definitely important for the protection of our environment. Solutions of tiny amounts of silver are extremely threatening to microbial life, which form an important part of our water ecosystems. It is therefore of utmost important that this is neutralized. Together with the chapter ‘Quality and Environmental Control’, this section discusses an important, often forgotten part of our photography hobby.

In terms of writing, this is probably one of the worst chapters in the book and would be the chapter to revise if there ever were to be a new edition. It contains duplicate text and information and some typesetting errors that make you wonder where the rest of the sentence has gone.

Other chapters

Some other chapters are worth mentioning here, without further discussion. The first concerns ‘After treatment of the negative’, which discusses reduction and intensification. These processes were already much less important in 1976 then they were today, but might be useful in rare instances to the roll film shooter and perhaps slightly more often to the sheet film fine-art photographer.
The same holds for the second worth mentioning, which is aptly named ‘Retouching’. For the amateur, most retouching will nowadays happen more in print, then it will on the negative.
The third, titled ‘Processing colour films’, offers an interesting overview of how colour processes work and some formulae. However, these chemicals involved are (extremely) hazardous to handle and their handling should, in my opinion, be left to the professionals.

General remarks

For a book written by scientists, I find it very light on references. To be frank, there aren’t any at all in the first half that I could find. Although in this part of the book the authors mention the names of the original authors of specific formulae, there are no references to specific publications. I personally find this a pity, as I would like to read more about specific formula and about the original results they obtained. Only in the second half, starting with the chapter on fixers, you will find occasional references to patents and papers and their original authors.

It is clear from the writing, that the first book was probably written by Kurt, while the second half was added later probably written by Ralph, but this is in no way annoying.


I find the book a very interested read and think this should be on your bookshelf if you have an interest in the chemistry of developing film and printing. The academic writing style did not bother me, but I can imagine this will require some getting used to for others. It covers many interesting aspects of black-and-white film development and provides insight in how the chemistry affects the final image.

About the authors

The original version was authored by Kurt I. Jacobson, an established name in the field of photographic chemistry, especially in the field of two- and three colour processing. Born in Germany in 1906, he emigrated to the UK in 1939. Through his company Photochemical Co Ltd, Dr. Jacobson’s name is associated with the Paterson company and later Pavelle Ltd. The latter was eventually bought and renamed to Durst (UK) Ltd. by the Italian Durst AG. There he developed both equipment and processes. dr. Ralph E. Jacobson later joined the company and worked with his father on the same topics. He later went on to become professor of imaging science at the university of Westminster, UK.

References:, Accessed May 7, 2016.

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